This example checks if a bx approach/tool can handle m2n relationships between elements.
In this particular case, Activities in CPM networks correspond both to Activities as well as Dependencies in Gantt diagrams.
This means that the backward direction is in general non-deterministic, but is to be controlled via additional "coding conventions".
In the diagram below (taken from ), simple class diagrams are used to show one possible representation of this scenario.
Gant diagrams correspond to CPM networks, CPM activities together with source and target events correspond to Gantt activities, and CPM activities with an "->" in their names correspond to Gantt dependencies.
A concrete example (from ) showing a consistent pair of a Gantt diagram (a) and a CPM network (b) is depicted below:
Out-of-scope for .
Properties [optional section]
Variants [optional section]
References [optional section]
This example is taken from the following paper:
 Westfechtel, Bernhard. "Case-based exploration of bidirectional transformations in QVT Relations." Software & Systems Modeling (2016): 1-41.
Bernhard Westfechtel, Anthony Anjorin
Artefacts [optional section]
An implementation with QVT-R can be taken from: Westfechtel, Bernhard. "Case-based exploration of bidirectional transformations in QVT Relations." Software & Systems Modeling (2016): 1-41.
An implementation with TGGs can be downloaded from here or viewed as diagrams here.
Note that both the paper and implementations focussed on "batch" forward and backward transformations and not on consistency restoration.